Fastener with floating nut

ABSTRACT

A fastener including a sleeve having a first flange at one end which extends radially outwardly and terminates in a portion extending longitudinally toward the opposite end of the sleeve for a limited distance, the opposite end of the sleeve being of reduced wall thickness and being adapted to be bent outwardly to form a second flange cooperating with the first flange in holding the sleeve to the workpiece when the sleeve has been inserted through an opening in the workpiece, a nut being received within the sleeve with clearance around its periphery, the nut having outwardly projecting tabs extending through slots in the sleeve into the space provided by the first flange, so that the nut is permitted limited lateral floating movement and precluded from substantial rotation, the bolt having a threaded shank with a pointed end for facilitating entry into the nut, and having a wide thin head provided with a central protrusion engaged by a tubular portion of the driving tool for aligning the driving tool with the head. The tubular portion of the driving tool is spring biased outwardly and is moved inwardly upon engagement with the head at the central portion thereof, while blades on the driving blade tool enter the slot in the bolt head.

United States Patent Burt [ 1 Feh.8,1972

[54] F ASTENER WITH FLOATING NUT [2]] Appl. No.: 35,853

[52] U.S. Cl ..l51/41.74, 151/4176, 85/9, 85/45 [51] Int. Cl ..Fl6b43/00 [58] Field ofSenrch l 5 l/4l.7, 41.72, 41.73, 41.74, l51/4I.75,41.76; 85/32 K, 45,1 P, 9

5n Relerences Cited UNITEDSTATES PATENTS 1,570,148 1/1926 Herr..151/41.74 1,749,547 3/1930 Ruddy ..85/45 2,243,923 6/1941 Swanstrom1S1/41.76 2,338,023 12/1943 Bugg ..85/45 Re22.543 9/1944 Tinnerman151/41.75 2,815,789 12/1957 Hutson et al... .151/41.7 2,986,188 5/1961Karp et Isl/41.73 3,131,743 5/1964 Hinkle et a1. ....15l/41.73 3,405,75210/1968 Neuschotz ..151/41.72

FOREIGN PATENTS OR APPLICATIONS 137,741 6/1950 Australia 483,089 4/1938Great Britain ..l5 l/4l.7

Primary Examiner-Marion Parsons, Jr. Attorney-Gausewitz, Carr &Rothenberg [57] ABSTRACT A fastener including a sleeve having a firstflange at one end which extends radially outwardly and terminates in aportion extending longitudinally toward the opposite end of the sleevefor a limited distance, the opposite end of the sleeve being of reducedwall thickness and being adapted to be bent outwardly to form a secondflange cooperating with the first flange in holding the sleeve to theworkpiece when the sleeve has been inserted through an opening in theworkpiece, a nut being received within the sleeve with clearance aroundits periphery, the nut having outwardly projecting tabs extendingthrough slots in the sleeve into the space provided by the first flange,so that the nut is permitted limited lateral floating movement andprecluded from substantial rotation, the bolt having a threaded shankwith a pointed end for facilitating entry into the nut, and having awide thin head provided with a central protrusion engaged by a tubularportion of the driving tool for aligning the driving tool with the head.The tubular portion of the driving too] is spring biased outwardly andis moved inwardly upon engagement with the head at the central portionthereof, while blades on the driving blade tool enter the slot in thebolt head.

12 Claims, 7 Drawing Figures FASTENER WITI'I FLOATING NUT BACKGROUND OFTHE INVENTION 1. Field of the Invention This invention relates tofasteners.

2. The Prior Art Helicopters and V'TOL craft are capable of operatingfrom landing mats which may be placed over terrain where there has beenno time-consuming construction of a conventional landing pad orairstrip. In one system, the landing mat is made up of an assembly offlat panels arranged in an overlapping pattern and secured together.These may be panels of glass fiber-reinforced plastic arranged in anoverlapping relationship. This has the advantage of permitting assemblyof a number of panels into a landing mat of desired size, while theindividual panels are readily transportable for use wherever needed. Thelanding mats may be installed or removed as the occasion demands simplyby assembling or disassembling the panels.

In order for the landing mat to be used to maximum advantage, there mustbe provided a means to rapidly yet securely attach the panels together.Conventional bolts obviously are not suitable because they requireaccess to both sides of the panel. Screws likewise are not satisfactorybecause the panels of the landing mat cannot provide threads of adequatestrength. A suitable fastener, therefore, preferably will have somemeans for attaching a nut to the bottom panel, where it is held againstrotation and prevented from separating when the panels are disassembled.Moreover, the nut should be permitted a large amount of lateral floatingmovement so that it can be engaged by the bolt even when the panels aremisaligned. The fasteners should provide only slight protrusions ateither end of attached panels, and not be vulnerable during handling orunder compression loads.

There have been provided in the past fasteners in which a nut is securedto a workpiece and allowed limited floating movement while beingprecluded from substantial rotation. In these designs, generally the nuthas projected from one side of the workpiece where it occupiesadditional volume and may be subject to damage during handling of theworkpiece. Fasteners of this type are shown in U.S. Pat Nos. 2,420,733,2,717,622, 2,815,789 and 2,972,367. Many of these fasteners are somewhatcomplex and expensive. Moreover, usually some cumbersome means, such asauxiliary rivets, are used to secure the nut assembly to the workpiece.In U.S. Pat. No. 3,389,736, a type of nut is held to a panel by aflanged sleeve, but this is for an axially movable nut that does notfloat laterally, rather than for an axially fixed nut with provision forlateral floating as needed for securing landing mat panels. Whereflanges overlap tab elements on the nuts to allow floating, as in U.S.Pat. Nos. 2,717,622 and 2,8I5,789, the flanges are not capable ofsupporting substantial exterior loads without bending inwardly so as tointerfere with the floating movement of the nut. The nut in U.S. Pat.No. 1,356,835 is buried within an opening in a workpiece, but theretaining cup has projecting spikes that must be driven into theworkpiece to be held by friction. Consequently, there is no positiveretention of the nut.

SUMMARY OF THE INVENTION The fastener arrangement of this inventionincludes a sleeve, within which is a nut having tabs which projectoutwardly through slots in the circumferential wall of the sleeve. Thelateral dimension of the nut is substantially less than the internaldiameter of the sleeve, and the tabs are narrower than the slots, sothat substantial lateral floating movement is permitted, while the tabsprevent the nut from more than limited rotational movement.

The sleeve includes a flange projecting outwardly in the radialdirection at one end, terminating in a radial outer portion thatprojects backwardly toward the opposite end of the sleeve for a limiteddistance. This provides an annular recess into which the ends of thetabs of the nut extend. The flange is of relatively thick cross section,so that it will withstand compression loads on the fastener withoutbending inwardly to interfere with the tabs and prevent the floatingmovement of the nut.

The sleeve is extended through an opening in a panel to bring the edgeof the flange into engagement with one panel surface, while the oppositeend of the sleeve projects beyond the other panel surface. Theprojecting end of the sleeve is of reduced wall thickness and adapted tobe bent outwardly to overlap the the other side of the panel tocooperate with the flange and form an attachment. It may be clampedsecurely against the panel surface so that the sleeve is prevented fromrotation. In this manner, the nut is mounted within the opening in thepanel with very little protrusion of the assembly beyond the panelsurfaces.

The bolt is extended through a clearance opening in the other panel andincludes a conical end on its threaded shank to facilitate entry of theshank into the threaded opening in the nut. The bolt has a wide thinhead that overlaps the outer surface of the panel with which it isassociated. A cross slot extends through the head for engagement by thedriving tool. At the central portion of the head is a short outwardprotrusion which is used in aligning the driving tool on the fastenerhead.

The driving tool includes a member terminating in a radial face, fromwhich extend two blade portions for entry into the driving slot in thefastener head. Between the blade portions is a tubular element, which isspring biased outwardly. This member is dimensioned to receive theprotrusion on the head of the fastener, thereby indexing the drivingtool in the fastener head and assuring that the blades will engage thedriving slot properly during the rotation of the bolt.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a perspective view of thefastener in the separated position;

FIG. 2 is a sectional view taken along line 22 of FIG. 1;

FIG. 3 is an enlarged longitudinal sectional view of the fastener in thesecured position holding together two panels;

FIG. 4 is a fragmentary plan view illustrating the arrangement oflanding mat panels to be secured by the fastener of this invention;

FIG. 5 is a perspective view of the driving tool;

FIG. 6 is a longitudinal sectional view of the driving tool; and

FIG. 7 is a longitudinal sectional view showing the driving tool inassociation with the bolthead.

DESCRIPTION OF THE PREFERRED EMBODIMENT The fastener of this inventionincludes a bolt 10 and a nut assembly 11. The bolt 10 includes a shank12, the end portion of which is threaded and terminates in a generallyconical end surface 13. At the opposite end of the shank I2 is a wide,relatively flat head 14. The head 14 has a greater diameter than that ofan ordinary screw or bolt and, at the same time, is considerably thinnerthan a conventional screw or bolthead. At

the center of the head 14 is a circular protrusion 15 that extends ashort distance from the head 14 in a direction opposite from that of theshank 12. A cross slot 16 extends diametrically through the outersurface of the head 14 and the protrusion 15.

The nut assembly 11 includes a collar 18, within which is a nut I9. Thecollar 18 includes a central tubular portion 20 which is circular incross section. Adjacent its outer end 21, the tubular portion isprovided with a counterbore 22 that extends inwardly a short distanceand provides an end portion 23 having a relatively thin wall.

At the opposite end of the tubular portion 20 is an integral outwardlyprojecting annular flange 24. The flange 24 extends radially from theend of the tubular section 20, terminating in a short cylindrical part25 that is coaxial with the tubular portion 20. The cylindrical part 25of the flange 24 extends toward the end 21 of the collar 18, but isconsiderably shorter than the tubular portion 20 of the collar.

Radially opposite the cylindrical portion 25 of the flange 24, thetubular portion of the collar 18 is provided with two relatively widediametrically opposed circumferential slots 27 through its wall. Theseslots receive a pair ofdiametrically oppositely projecting tabs 28 onone end of the nut 19. The tabs 28 have considerably less width than theslots 27. The overall distance between the outer ends of the tabs 28 issubstantially less than the internal diameter of the cylindrical portion25 of the flange 24.

The central portion 30 of the nut 19 has a cylindrical exterior surfacewith a diameter somewhat less than the interior diameter of the tubularportion 20 of the collar 18. A threaded bore 31 extends through the nut19. With the tabs 28 being at one end of the nut and received in slotsat one end of the tubular portion 20 of the collar 18, the nut is heldentirely within the collar between its opposite ends.

With the portion 30 of the nut being of lesser diameter than theinterior of the tubular portion 20 of the collar, and the tabs 28narrower than the slots 27, the nut 19 is permitted a large amount offloating movement relative to the collar 18. It may move laterally inany direction to bring the periphery of the cylindrical portion 30 ofthe nut into adjacency with the inner wall of the tubular portion 20 ofthe collar. At the same time, the tabs 28 will engage the edges of theslots 27 to limit rotational movement ofthe nut 19 relative to thecollar 18.

In use ofthe fastener, the nut assembly 11 is associated with oneworkpiece 32, while the bolt is extended through the other workpiece 33.Typically, the workpieces 32 and 33 are panels of a landing matassembly. These may be made of glass fiber reinforced plastic aroundthree-eighths inch thick and 3 feet by 6 feet in plan. These panels maybe arranged in an edge-toedge abutting relationship in two layers, asshown in FIG. 4. Thus, on the bottom are the panels 32 with theiradjacent edges in contact. The upper panels 33 are superimposed on thelower panels 32 and in a staggered relationship with the lower panels.In completing a landing mat, it is necessary to secure the panels 32 and33 together to provide a unitary structure, which may be accomplished bypositioning fasteners at the corners, as indicated in FIG. 4.

When the nut assembly 11 is attached to the panel 32, an opening 34 isprovided in the panel, through which the tubular portion of the collar18 is extended. The fastener and panel are proportioned such that, whenthe radial edge surface of the outer portion of the flange 24 is broughtinto engagement with one outer surface 36 of the panel 32, the endportion 23 of the collar 18 projects beyond the opposite outer surface37 of the panel 32. The thin-walled portion 23 of the collar then isbent outwardly to form a flange 38 that overlaps the opposite surface 37of the panel 32, cooperating with the flange 24 in retaining the nutassembly 11 to the workpiece, as seen in FIG. 3. The flange 38 may beclamped firmly against the surface 37 of the panel 32 so that the nutassembly is frictionally held against rotation relative to the panel.When the nut assembly 11 is so secured to the panel 32, an annular space39 is provided between the flange 24 and the outer surface 36 of thepanel 32. This provides a clearance so that there is no interferencewith the tabs 28, and the nut 19 is not restrained in its floatingmovement relative to the collar 18.

An oversize opening 41 is formed in the panel 33 to receive the shank 12of the bolt 10. With the head 14 being of wide diameter, it will overlapthe outer surface 42 of the panel 33, irrespective of the lateralposition of the bolt 10 within the opening 41. Therefore, the bolt 10also is allowed considerable lateral floating movement. This permits thebolt and nut to be mated despite considerable misalignment of theopenings through the panels 32 and 33. The tapering conical end 13 ofthe shank 12 facilitates the entry of the shank into the threaded bore31 of the nut 19 and permits the threads to become engaged.

When the bolt 10 is advanced into the nut 19 to hold the panels 32 and33 together, the flat nut 14 provides only a small protrusion above theouter surface 42 of the panel 33. Similarly, the flange 24 extends downbelow the surface 36 of the lower panel 32 only a short distance. Thenut 19 is substantially buried in the opening 34 in the panel 32. Thenut assembly is protected both during handling and use of the landingmat panels. The nut 19 will retain its ability to float laterally tofacilitate engagement of the fastener because the tabs 28 are protectedby the flange 24. The latter element is fully supported around its outerperimeter by the surface 35 and at its inner edge by the tubular section20 of the collar. Relatively large exterior forces may be imposedwithout causing the flange 24 to be bent inwardly to engage the tabs 28.

In order to facilitate the driving of the bolt 10 with its wide flathead, preferably a special driving tool 44 is utilized (see FIGS. 5, 6and 7). This tool includes a cylindrical body 45 having a radial endface 46 from which driving blades 47 and 48 project longitudinally.These blades extend radially inwardly from opposite circumferentialedges of the driver and provide the wrenching surfaces that are adaptedto engage the boltwrenching surfaces defined by the slot 16. With theblades 47 and 48 in the slot 16, the body 45 may be rotated in anysuitable manner to turn the bolt 10 and drive the fastener. There may bea hexagonal portion 49 on the body 45, as illustrated in FIG. 5, or thetool may be connected in any appropriate manner to a power-operateddevice for rotating it.

Between the blades 47 and 48, an opening 51 extends axially inwardlyfrom the outer radial face 46 of the driver body 45. A transverse wall52 is at the inner end of the opening 51, having a central opening 53 ofsmaller diameter which leads to a larger end opening 54. A plunger 56 isreceived in the openings 51, 53 and 54. It includes an end portion 57having a circumferential wall that is substantially complementary to theopening 51, and which is provided with a bore 58 in its outer end 59.The end portion 57 is between the blades 47 and 48, which are positionedradially with respect to the plunger. The interior diameter of the bore58 is just slightly larger than the diameter of the protrusion 15 on thehead 14 of the bolt 10. A stem 60 extends from the portion 57 of theplunger 56, passing through the opening 53 into the opening 54, where itis threaded and engaged by a nut 61. A compression spring 62 bearsagainst the transverse wall 52 and against the suitable 63 between theportion 57 and the stem 60 of the plunger 56. This biases the plunger 56outwardly with respect to the end 46 of the body 45, bringing the nut 60into engagement with the wall 52. In this position, the end 59 of theplunger 56 extends outwardly in the axial direction a short distancepast the blades 47 and 48.

In use of the driving tool 44, it is brought against the outer end ofthe head 14 of the bolt 10. The protrusion 15 will enter the opening 58,as shown in FIG. 7, centering the tool 44 with respect to the fastener.Axial pressure against the driver 44 overcomes the force of the spring62 and pushes the plunger 56 axially inwardly so that the blades 47 and48 are moved against the bottom of the slot 16. The driver 44 is rotatedin the usual manner to turn the bolt 10. During this rotation, thepresence of the protrusion 15 of the head in the bore 58 maintains thedriver and fastener in proper alignment so that the blades 47 and 48will not slip out of the slot 16.

The foregoing detailed description is to be clearly understood as givenby way of illustration and example only, the spirit and scope of thisinvention being limited solely by the appended claims.

What is claimed is:

1. A floating nut device comprising a member having a tubular portionand an integral flange at one end of said tubular portion,

said flange having a first portion extending generally radiallyoutwardly from said tubular portion,

and a second portion extending generally longitudinally toward theopposite end of said tubular portion and terminating in a substantiallyradial edge adapted to engage a workpiece,

said first and second portions defining a recess,

a nut received in said tubular portion,

said tubular portion having a greater internal lateral dimension thanthe external lateral dimension of said nut,

tend radially with respect to said nut at one end thereof.

said substantially radial edge thereof are annular.

of said tubular portion is bendable outwardly for forming a secondflange for cooperating with said first-mentioned flange in holding saidmember to a workpiece.

3. A device as recited in claim 2 in which said tubular portion at saidopposite end is of reduced wall thickness for facilitating the outwardbending of said second flange.

4. A device as recited in claim 2 in which said tab means ex- 5. Adevice as recited in claim 4 in which said nut is received entirelywithin said member.

6. A device as recited in claim 3 in which said flange and 7. A deviceas recited in claim 6 in which said aperture means includes a pair ofdiametrically opposed circumferential slots in said tubular portion,said slots being radially opposite said second portion of said flange,and said tab means include a pair of tabs,

said tabs extending radially from said nut in opposite directions at oneend of said nut, said tabs being received in said slots, said tabs beingnarrower than said slots, the dimension between the outer ends of saidtabs being less than the internal diameter of said second portion ofsaid flange. 8. A device as recited in claim 7 including in addition abolt for engagement with said nut, said bolt having a threaded shankterminating in a substantially conical end for facilitating entry ofsaid shank into said nut.

9. A device as recited in claim 8 in which said bolt includes arelatively wide thin head.

10. A device as recited in claim 9 in which said nut includes a centralprotrusion extending outwardly from the outer surface of said head foruse in aligning a driving tool on said head. 11. in combination with aworkpiece having an opening therethrough, a first surface at one end ofsaid opening and a second surface at the opposite end of said opening. anut device comprising a member having a tubular portion extendingthrough said opening.

a first flange at one end of said tubular member extending outwardly andoverlapping said first surface,

a second flange at the opposite end of said tubular portion, said secondflange having a first portion extending generally radially outwardlyfrom said tubular portion, said first portion being spaced outwardlyfrom said second surface,

and a second portion extending from the outer edge of said first portiongenerally longitudinally toward said one end of said tubular portion,

said second portion terminating in a substantially radial edge engagingsaid second surface for cooperating with said first flange in holdingsaid member to said workpiece, said first and second portions defining arecess,

and a nut received in said tubular portion,

said nut including outwardly projecting tab means, said tubular portionhaving aperture means therethrough located axially between said firstportion of said flange and said substantially radial edge,

said tab means extending through said aperture means into said recessfor retaining said nut to said member and preventing substantialrotation of said nut relative to said member, said tubular portionhaving a greater rntemal lateral posed slots larger than said tabs so asto provide a clearance around said tabs.

1. A floating nut device comprising a member having a tubular portionand an integral flange at one end of said tubular portion, said flangehaving a first portion extending generally radially outwardly from saidtubular portion, and a second portion extending generally longitudinallytoward the opposite end of said tubular portion and terminating in asubstantially radial edge adapted to engage a workpiece, said first andsecond portions defining a recess, a nut received in said tubularportion, said tubular portion having a greater internal lateraldimension than the external lateral dimension of said nut, and outwardlyprojecting tab means on said nut, said tubular portion having aperturemeans therethrough radially inwardly said second portion of said flange,and axially between said first portion of said flange and said radialedge, said tab means extending through said aperture means and beingreceived in said recess adjacent said first and second portions of saidflange, whereby said nut is permitted lateral floating movement whilesaid tab means preclude substantial rotation of said nut.
 2. A device asrecited in claim 1 in which the opposite end of said tubular portion isbendable outwardly for forming a second flange for cooperating with saidfirst-mentioned flange in holding said member to a workpiece.
 3. Adevice as recited in claim 2 in which said tubular portion at saidopposite end is of reduced wall thickness for facilitating the outwardbending of said second flange.
 4. A device as recited in claim 2 inwhich said tab means extend radially with respect to said nut at one endthereof.
 5. A device as recited in claim 4 in which said nut is receivedentirely within said member.
 6. A device as recited in claim 3 in whichsaid flange and said substantially radial edge thereof are annular.
 7. Adevice as recited in claim 6 in which said aperture means includes apair of diametrically opposed circumferential slots in said tubularportion, said slots being radially opposite said second portion of saidflange, and said tab means include a pair of tabs, said tabs extendingradially from said nut in opposite directions at one end of said nut,said tabs being received in said slots, said tabs being narrower thansaid slots, the dimension between the outer ends of said tabs being lessthan the internal diameter of said second portion of said flange.
 8. Adevice as recited in claim 7 including in addition a bolt for engagementwith said nut, said bolt having a threaded shank terminating in asubstantially conical end for facilitating entry of said shank into saidnut.
 9. A device as recited in claim 8 in which said bolt includes arelatively wide thin head.
 10. A device as recited in claim 9 in whichsaid nut includes a central protrusion extending outwardly from theouter surface of said head for use in aligning a driving tool on saidhead.
 11. In combination with a workpiece having an openingtherethrough, a first surface at one end of said opening and a secondsurface at the opposite end of said opening, a nut device comprising amember having a tubular portion extending through said opening, a firstflange at one end of said tubular member extending outwardly andoverlapping said first surface, a second flange at the opposite end ofsaid tubular portion, said second flange having a first portionextending generally radially outwardly from said tubular portion, saidfirst portion being spaced outwardly from said second surface, and asecond portion extending from the outer edge of said first portiongenerally longitudinally toward said one end of said tubular portion,said second portion terminating in a substantially radial edge engagingsaid second surface for cooperating with said first flange in holdingsaid member to said workpiece, said first and second portions defining arecess, and a nut received in said tubular portion, said nut includingoutwardly projecting tab means, said tubular portion having aperturemeans therethrough located axially between said first portion of saidflange and said substantially radial edge, said tab means extendingthrough said aperture means into said recess for retaining said nut tosaid member and preventing substantial rotation of said nut relative tosaid member, said tubular portion having a greater internal lateraldimension than the external lateral dimension of the body of said nut,said second portion of said second flange having a greater internallateral dimension than the lateral dimension of said tab means, wherebysaid nut is permitted lateral floating movement relative to said sleeve.12. A device as recited in claim 11 in which said tab means includes apair of diametrically oppositely extending flat tabs, and said aperturemeans includes a pair of diametrically opposed slots larger than saidtabs so as to provide a clearance around said tabs.